Reinsurance - Variable Interest Entity (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2019	Dec. 31, 2018
Home Re special purpose insurers
Effects of Reinsurance [Line Items]
Term of mortgage insurance-linked notes	10 years
Remaining First Layer Retention	$ 353,826
Remaining Excess of Loss Reinsurance Coverages	604,591
Home Re 2018-1
Effects of Reinsurance [Line Items]
Remaining First Layer Retention	168,112
Remaining Excess of Loss Reinsurance Coverages	288,852
Total VIE Assets	299,655	$ 318,636
Home Re 2019-1
Effects of Reinsurance [Line Items]
Remaining First Layer Retention	185,714
Remaining Excess of Loss Reinsurance Coverages	315,739
Total VIE Assets	$ 315,739

Reinsurance Retention Policy, Debt Issued To Cover Insurance, Term

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- Definition

Reinsurance Retention Policy, Remaining Excess of Loss Reinsurance Coverages

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Stated amount that is the upper retention limit per entity policy.

+ References

No definition available.

+ Details

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- Definition

Carrying amount of the assets in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph a
-URI http://asc.fasb.org/extlink&oid=118582676&loc=d3e5728-111685

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